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Polar body
 
 
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A polar body is a cell
Cell (biology)

The cell is the structural and functional unit of all known Life organisms. It is the smallest unit of an organism that is classified as living, and is often called the building bricks of life....
 structure found inside an ovum
Ovum

An ovum is a haploid female reproductive cell or gamete. Both animals and embryophytes have ova. The term ovule is used for the young ovum of an animal, as well as the plant structure that carries the female gametophyte and egg cell and develops into a seed after fertilization....
. Both animal
Animal

Animals are a major group of multicellular, eukaryotic organisms of the Kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life....
 and plant
Plant

Plants are Life organisms belonging to the Kingdom Plantae. They include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae....
 ova possess it. It is also known as a polar cell.

Asymmetrical cell division (cytokinesis
Cytokinesis

Cytokinesis is the process where the cytoplasm of a single eukaryotic cell is divided to form two daughter cells. It usually initiates during the late stages of mitosis, and sometimes meiosis, splitting a binucleate cell in two, to ensure that chromosome number is maintained from one generation to the next....
) leads to the production of polar bodies during oogenesis
Oogenesis

Oogenesis or rarely o?genesis is the creation of an ovum . It is the female process of gametogenesis. It involves the various stages of immature ova....
. To conserve nutrients, the majority of cytoplasm
Cytoplasm

The cytoplasm is the part of a Cell that is enclosed within the plasma membrane. In eukaryote cells the cytoplasm contains organelles, such as mitochondrion, that are filled with liquid kept separate from the rest of the cytoplasm by biological membranes....
 is segregated into either the secondary oocyte
Oocyte

An oocyte, ovocyte, or rarely ocyte, is a female gametocyte or germ cell involved in biological reproduction. In other words, it is an immature ovum, or ovum cell....
 or ovum, during meiosis
Meiosis

In biology or life science, meiosis is a process of reductional division in which the number of chromosomes per cell is halved. In animals, meiosis always results in the formation of gametes, while in other organisms it can give rise to spores....
 I or meiosis II, respectively.






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Gray9
A polar body is a cell
Cell (biology)

The cell is the structural and functional unit of all known Life organisms. It is the smallest unit of an organism that is classified as living, and is often called the building bricks of life....
 structure found inside an ovum
Ovum

An ovum is a haploid female reproductive cell or gamete. Both animals and embryophytes have ova. The term ovule is used for the young ovum of an animal, as well as the plant structure that carries the female gametophyte and egg cell and develops into a seed after fertilization....
. Both animal
Animal

Animals are a major group of multicellular, eukaryotic organisms of the Kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life....
 and plant
Plant

Plants are Life organisms belonging to the Kingdom Plantae. They include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae....
 ova possess it. It is also known as a polar cell.

Asymmetrical cell division (cytokinesis
Cytokinesis

Cytokinesis is the process where the cytoplasm of a single eukaryotic cell is divided to form two daughter cells. It usually initiates during the late stages of mitosis, and sometimes meiosis, splitting a binucleate cell in two, to ensure that chromosome number is maintained from one generation to the next....
) leads to the production of polar bodies during oogenesis
Oogenesis

Oogenesis or rarely o?genesis is the creation of an ovum . It is the female process of gametogenesis. It involves the various stages of immature ova....
. To conserve nutrients, the majority of cytoplasm
Cytoplasm

The cytoplasm is the part of a Cell that is enclosed within the plasma membrane. In eukaryote cells the cytoplasm contains organelles, such as mitochondrion, that are filled with liquid kept separate from the rest of the cytoplasm by biological membranes....
 is segregated into either the secondary oocyte
Oocyte

An oocyte, ovocyte, or rarely ocyte, is a female gametocyte or germ cell involved in biological reproduction. In other words, it is an immature ovum, or ovum cell....
 or ovum, during meiosis
Meiosis

In biology or life science, meiosis is a process of reductional division in which the number of chromosomes per cell is halved. In animals, meiosis always results in the formation of gametes, while in other organisms it can give rise to spores....
 I or meiosis II, respectively. The remaining daughter cells generated from the meiotic events contain relatively little cytoplasm and are referred to as polar bodies. Eventually, the polar bodies degenerate.

There may be 1 or two polar bodies in the ovum of plant cells (though animal cells may possibly possess it). The first polar body is one of the two products in the first stage of meiosis and is considered diploid, with 46 chromatids (23 chromatids that have been duplicated), whereas the second polar body contains only one of each chromatid
Chromatid

A chromatid is one among the two identical copies of DNA making up a replicated chromosome, which are joined at their centromeres, for the process of cell division ....
, (23 chromatids) and is haploid. Both are relatively small and contain little cytoplasm. Sometimes the first polar body undergoes the second meiotic cell division.

Some say that this second polar body can potentially result in half-identical twins
Half twin

Semi-identical twins are the result of a very rare form of twin in which the twins inherit exactly the same genes from their mother but different genes from their father....
, when the second polar body does not disintegrate and is fertilized by a sperm
Spermatozoon

A sperm, from the ancient Greek word sp???a and and more commonly known as a sperm cell, is the ploidy cell that is the male gamete. It Fertilization an ovum to form a zygote....
; but such development would usually be impossible because it does not have enough cytoplasm (and yolk, if the ovum has yolk) to feed the developing embryo.

In plants, the pollen
Pollen

Pollen is a fine to coarse powder consisting of Gametophyte , which produce the male gametes of spermatophyta. A hard coat covering the pollen grain protects the sperm cells during the process of their movement between the stamens of the flower to the pistil of the next flower....
 releases two male gametes (sperm
Sperm

The term sperm is derived from the Greek word sperma and refers to the male reproductive Cell . In the types of sexual reproduction known as anisogamy and oogamy, there is a marked difference in the size of the gametes with the smaller one being termed the "male" or sperm cell....
 nuclei) into the ovule
Ovule

Ovule literally means "small ovum." In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: The integuments forming its outer layer, the nucellus , and the megaspore-derived female gametophyte in its center....
 upon fertilization. One fertilizes the haploid ovum and develops into a normal embryo, while the other fertilizes the two polar bodies within the center of the ovary, creating a structure called endosperm
Endosperm

Endosperm is the tissue produced in the seeds of most flowering plants around the time of fertilization. It surrounds the embryo and provides nutrition in the form of starch, though it can also contain Vegetable oils and protein....
. Endosperm stores nutrients for initial growth of plant seed
Seed

A seed is a small Plant embryogenesis plant enclosed in a covering called the seed coat, usually with some Food storage. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant....
s. Cereal grain
Cereal

Cereals, or cereal grains, are mostly Poaceae cultivated for their edible brans or fruit seeds . Cereal grains are grown in greater quantities and provide more energy worldwide than any other type of crop; they are therefore staple foods....
 is an example of this, and is consumed for its nutritional value by many animals, including humans.

Polar bodies are the by-products of the egg’s division during meiosis
Meiosis

In biology or life science, meiosis is a process of reductional division in which the number of chromosomes per cell is halved. In animals, meiosis always results in the formation of gametes, while in other organisms it can give rise to spores....
. As an egg matures, it goes through a two-step division process, dividing once at the time when ovulation would occur and again at the time of fertilization. The three haploid polar bodies are the by-products of this division, and are essentially discarded by the egg. By analyzing the polar bodies, it is possible to infer the genetic status of the egg. Therefore, polar body analysis allows us to test the mother’s genetic contribution to the embryo.

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